Dural Arteriovenous Fistulae in the Tentorium Manifesting as Dementia

BACKGROUND: Tentorial dural arteriovenous fistula(dAVF)is a relatively rare disease which accounts for about 4.8% of all types of dAVF reported in Japan. Approximately 12.5% of intracranial dAVFs manifest with dementia-like symptoms. However, a tentorial dAVF typically presents more aggressively and rarely manifests as dementia. Here, we report the case of a patient with a tentorial dAVF manifesting as dementia, who was successfully treated with surgical interruption of the draining vein using indocyanine green video angiography(ICG-VA). CASE PRESENTATION: A case of a 69-year-old man with a history of colon cancer, hypertension, and previous stroke presenting with cognitive impairment. CT showed multiple intracranial hemorrhages in the left parietal and occipital lobes, and MRI demonstrated flow void in the left cerebellopontine angle. DSA revealed left tentorial dAVF with venous reflux. We performed surgical interruption of the draining vein. The patient's mental status immediately returned to baseline. Serial MRIs showed decreasing edema in the left occipital lobe and thalamus. CONCLUSIONS: Cognitive impairment is an uncommon but curable symptom of tentorial dAVF. Surgical interruption of the draining vein using ICG-VA is a relatively simple and safe procedure to perform in such a case.